In recent years, IZO (indium zinc oxide) has been used as wiring for circuit members instead of ITO (indium tin oxide), which is expensive to produce. IZO wiring has a smooth surface, and an oxide layer (passive) is formed on the surface. In addition, in aluminum wiring, for example, a protective layer made of an oxide layer such as TiO2 may be formed on the surface in order to prevent corrosion.
However, since oxide layers are hard, electrically conductive particles do not pierce and sufficiently penetrate the oxide layer of a conventional electrically conductive material, so sufficient conduction reliability cannot be achieved.